function sendEvent()

in src/Terminal.ts [869:946]
62 lines of code
17 McCabe index (conditional complexity)

    function sendEvent(button: number, pos: {x: number, y: number}): void {
      // self.emit('mouse', {
      //   x: pos.x - 32,
      //   y: pos.x - 32,
      //   button: button
      // });

      if (self._vt300Mouse) {
        // NOTE: Unstable.
        // http://www.vt100.net/docs/vt3xx-gp/chapter15.html
        button &= 3;
        pos.x -= 32;
        pos.y -= 32;
        let data = C0.ESC + '[24';
        if (button === 0) data += '1';
        else if (button === 1) data += '3';
        else if (button === 2) data += '5';
        else if (button === 3) return;
        else data += '0';
        data += '~[' + pos.x + ',' + pos.y + ']\r';
        self.handler(data);
        return;
      }

      if (self._decLocator) {
        // NOTE: Unstable.
        button &= 3;
        pos.x -= 32;
        pos.y -= 32;
        if (button === 0) button = 2;
        else if (button === 1) button = 4;
        else if (button === 2) button = 6;
        else if (button === 3) button = 3;
        self.handler(C0.ESC + '['
                  + button
                  + ';'
                  + (button === 3 ? 4 : 0)
                  + ';'
                  + pos.y
                  + ';'
                  + pos.x
                  + ';'
                  // Not sure what page is meant to be
                  + (<any>pos).page || 0
                  + '&w');
        return;
      }

      if (self.urxvtMouse) {
        pos.x -= 32;
        pos.y -= 32;
        pos.x++;
        pos.y++;
        self.handler(C0.ESC + '[' + button + ';' + pos.x + ';' + pos.y + 'M');
        return;
      }

      if (self.sgrMouse) {
        pos.x -= 32;
        pos.y -= 32;
        self.handler(C0.ESC + '[<'
                  + (((button & 3) === 3 ? button & ~3 : button) - 32)
                  + ';'
                  + pos.x
                  + ';'
                  + pos.y
                  + ((button & 3) === 3 ? 'm' : 'M'));
        return;
      }

      const data: number[] = [];

      encode(data, button);
      encode(data, pos.x);
      encode(data, pos.y);

      self.handler(C0.ESC + '[M' + String.fromCharCode.apply(String, data));
    }